Table of Contents

Content Settings

Block Pop-up Windows: By default, Firefox blocks annoying pop-up windows on websites. Unchecking this optionpreference will disable pop-up blocking. Some websites make legitimate use of pop-up windows. Therefore, you can allow these sites to open pop-ups anyway. To do so, click Exceptions…, enter the site name, and click Allow. To remove a website from the list, select it and then click Remove Site. To clear the list completely, click Remove All Sites. For more information, see the Pop-up blocker settings, exceptions and troubleshooting article.

Load images automatically: Firefox displays images in web pages by default. Uncheck this optionpreference to disable images in web pages. If you enable loading images automatically, the Exceptions… button lets you select sites from which images will not automatically load. The Exceptions… button lets you specify websites that you wish to load (or not load) regardless of the setting of this optionpreference. In the exceptions list, enter the site from which you want to allow or block images and click Allow to allow images, or click Block to block the images.

Enable JavaScript: JavaScript is a scripting language commonly used to make web pages interactive. However, it also makes certain annoying behaviors much easier to perform. To disable JavaScript, uncheck this optionpreference. However, note that disabling JavaScript may cause some sites to not work properly. For more fine-grained control over what JavaScript can and cannot do, click Advanced….

Advanced JavaScript Settings

Move or resize existing windows: Uncheck this optionpreference to disable moving and resizing windows using scripts.

Raise or lower windows: Uncheck this optionpreference to make sure scripts cannot raise (bring to the front) or lower (send to the back) windows.

Disable or replace context menus: Uncheck this optionpreference to prevent web pages from disabling or changing the Firefox context menu.

Fonts & Colors

Default font and Size: Web pages are usually displayed in the font and size specified here (measured in pixels). However, web pages can override these choices unless you specify otherwise in the Fonts dialog. Click the Advanced… button to access the Fonts dialog and to change this and other fonts optionspreferences.

Fonts Dialog

From the Fonts for drop-down list, choose a language group/script. For instance, to set default fonts for the West European languages/scripts (Latin), choose Western. For a language/script not in the list, choose Other Languages.

Select whether proportional text should be serif (like "Times New Roman") or sans-serif (like "Arial"). Then specify the font size you want for proportional text.

Specify the font to use for Serif, Sans-serif and Monospace fonts. You can also change the size for Monospace fonts.

You can also set the minimum web page font size. This is useful to prevent sites from using overly small fonts that are barely readable.

Allow pages to choose their own fonts, instead of my selections above: By default Firefox uses the fonts specified by the web page author. Disabling this optionpreference will force all sites to use your default fonts instead.

Character EncodingCharacter Encoding for Legacy Content: The character encoding selected here will be used to display pages that don't specify which encoding to use.

Colors Dialog

Text and Background: Here you can change the default text and background color to be used on web pages that haven't specified that information. Click on the color samples to select colors.

Use system colors Check this optionpreference to use the colors defined in your operating system settings instead of the colors specified above.

Link Colors: Here you can change the default colors for Web links. Click on the color samples to select colors.

Underline links: By default, links are underlined on web pages. Uncheck this optionpreference to disable this. Note that many sites specify their own styling rules and this optionpreference has no effect on those sites.

Allow pages to choose their own colors, instead of my selections above: By default, Firefox uses the colors specified by the web page author. Disabling this optionpreference will force all sites to use your default colors instead.

Languages

Some web pages are offered in more than one language. Click the Choose… button to specify your preferred language or languages.

Languages Dialog: To add a language, click Select a language to add…, choose the language, and click the Add button. Remove a language by selecting it in the list of active languages and clicking the Remove button. You can also reorder languages using the Move Up and Move Down buttons to determine the most preferred one in case a page is provided in multiple languages.